[libgames-support] scores: Make Importer an abstract class and add DirectoryImporter

[Michael Catanzaro <mcatanzaro src gnome org>]

commit 06a90ae62913892a9211a290f854a09d965492c7
Author: Michael Catanzaro <mcatanzaro igalia com>
Date:   Sat Feb 13 15:10:51 2016 -0600

    scores: Make Importer an abstract class and add DirectoryImporter

 games/Makefile.am                    |   13 +++---
 games/scores/directory-importer.vala |   81 ++++++++++++++++++++++++++++++++++
 games/scores/importer.vala           |   77 +++-----------------------------
 3 files changed, 95 insertions(+), 76 deletions(-)
---
diff --git a/games/Makefile.am b/games/Makefile.am
index c34a444..b41dfd7 100644
--- a/games/Makefile.am
+++ b/games/Makefile.am
@@ -1,12 +1,13 @@
 lib_LTLIBRARIES = libgames-support.la
 
 libgames_support_la_SOURCES = \
-       config.vapi             \
-       gridframe.vala          \
-       scores/category.vala    \
-       scores/context.vala     \
-       scores/dialog.vala      \
-       scores/importer.vala    \
+       config.vapi                     \
+       gridframe.vala                  \
+       scores/category.vala            \
+       scores/context.vala             \
+       scores/dialog.vala              \
+       scores/directory-importer.vala  \
+       scores/importer.vala            \
        scores/score.vala
 
 libgames_support_la_CFLAGS = \
diff --git a/games/scores/directory-importer.vala b/games/scores/directory-importer.vala
new file mode 100644
index 0000000..946a381
--- /dev/null
+++ b/games/scores/directory-importer.vala
@@ -0,0 +1,81 @@
+/* -*- Mode: vala; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ *
+ * Copyright © 2016 Michael Catanzaro <mcatanzaro gnome org>
+ *
+ * This file is part of libgames-scores.
+ *
+ * libgames-scores is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * libgames-scores is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with libgames-scores.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+namespace Games {
+namespace Scores {
+
+/* Imports scores from an old scores directory, where each category of scores is
+ * saved in a separate file. This is the format used by old C games that were
+ * never converted to Vala before switching to libgames-support. This class
+ * should probably be used by Five or More, Nibbles, Robots, Tali, and nothing
+ * else.
+ */
+public class DirectoryImporter : Importer
+{
+    /* A function provided by the game that converts the old category key to a
+     * new key. If the keys have not been changed, this function should return
+     * the same string. If the key is invalid, it should return null, as this
+     * function will be called once for each file in the game's local data
+     * directory, and some of those files might not be valid categories.
+     */
+    public delegate string? CategoryConvertFunc (string old_key);
+    private CategoryConvertFunc category_convert;
+
+    public DirectoryImporter (CategoryConvertFunc category_convert)
+    {
+        this.category_convert = category_convert;
+    }
+
+    /* This scores format is mostly-compatible with the current format, the only
+     * differences are (a) the scores file nowadays has a column for the player
+     * name, (b) scores nowadays are kept under ~/.local/share/APPNAME/scores
+     * whereas they used to be saved one level up, and (c) some category names
+     * have changed. All we have to do here is copy the files from the parent
+     * directory to the subdirectory, and rename them according to the new
+     * category names. Context.load_scores_from_file handles the missing player
+     * name column by assuming it matches the current UNIX account if missing.
+     * Notice that we are importing only home directory scores, not any scores
+     * from /var/games, since it's been several years since scores were removed
+     * from there and most players will have lost them by now anyway.
+     */
+    protected override void importOldScores (File new_scores_dir) throws GLib.Error
+    {
+        var original_scores_dir = new_scores_dir.get_parent ();
+        assert (original_scores_dir != null);
+
+        var enumerator = original_scores_dir.enumerate_children (FileAttribute.STANDARD_NAME, 0);
+        FileInfo file_info;
+        while ((file_info = enumerator.next_file ()) != null)
+        {
+            var new_key = category_convert (file_info.get_name ());
+            if (new_key == null)
+                continue;
+
+            var new_file = new_scores_dir.get_child (new_key);
+            var original_file = original_scores_dir.resolve_relative_path (file_info.get_name ());
+            debug ("Moving scores from %s to %s", original_file.get_path (), new_file.get_path ());
+            original_file.copy (new_file, FileCopyFlags.NONE);
+            original_file  delete ();
+        }
+    }
+}
+
+} /* namespace Scores */
+} /* namespace Games */
diff --git a/games/scores/importer.vala b/games/scores/importer.vala
index 80d6441..5341029 100644
--- a/games/scores/importer.vala
+++ b/games/scores/importer.vala
@@ -45,7 +45,8 @@ namespace Scores {
  * because it turns out people share user accounts and want to record scores
  * separately.
  *
- * This importer exists so that we don't delete everyone's scores a second time.
+ * These importers exist so that we don't delete everyone's scores a second
+ * time.
  *
  * Some users have complained that scores are now saved in the home directory.
  * Using /var/games was a clever setup and it's a bit of a shame to see it go;
@@ -57,78 +58,14 @@ namespace Scores {
  * don't plan to spend more time on this, though.
  */
 
-/* Note that all file I/O here is performed synchronously, because the importer
- * is only used before scores are loaded, and the library ensures scores are
- * always loaded before showing the main window.
+/* Note that importers must operate synchronously. This is fine because the
+ * importer is only used before scores are loaded, and we ensure scores are
+ * loaded before showing the main window.
  */
 
-public class Importer
+public abstract class Importer
 {
-    public enum OldFormat
-    {
-        C_GAMES_MULTI_FILE_FORMAT,
-        VALA_GAMES_SINGLE_FILE_FORMAT,
-    }
-
-    /* A function provided by the game that converts the old category key to a
-     * new key. If the keys have not been changed, this function should return
-     * the same string. If the key is invalid, it should return null, as this
-     * function will be called once for each file in the game's local data
-     * directory, and some of those files might not be valid categories.
-     *
-     * FIXME: Is this only useful for C_GAMES_MULTI_FILE_FORMAT?
-     */
-    public delegate string? CategoryConvertFunc (string old_key);
-    private CategoryConvertFunc category_convert;
-
-    private OldFormat format;
-
-    public Importer (OldFormat format, CategoryConvertFunc category_convert)
-    {
-        this.format = format;
-        this.category_convert = category_convert;
-    }
-
-    /* This scores format is mostly-compatible with the current format, the only
-     * differences are (a) the scores file nowadays has a column for the player
-     * name, (b) scores nowadays are kept under ~/.local/share/APPNAME/scores
-     * whereas they used to be saved one level up, and (c) some category names
-     * have changed. All we have to do here is copy the files from the parent
-     * directory to the subdirectory, and rename them according to the new
-     * category names. Context.load_scores_from_file handles the missing player
-     * name column by assuming it matches the current UNIX account if missing.
-     * Notice that we are importing only home directory scores, not any scores
-     * from /var/games, since it's been several years since scores were removed
-     * from there and most players will have lost them by now anyway.
-     */
-    private void importCMultiFileScores (File new_scores_dir) throws GLib.Error
-    {
-        var original_scores_dir = new_scores_dir.get_parent ();
-        assert (original_scores_dir != null);
-
-        var enumerator = original_scores_dir.enumerate_children (FileAttribute.STANDARD_NAME, 0);
-        FileInfo file_info;
-
-        while ((file_info = enumerator.next_file ()) != null)
-        {
-            var new_key = category_convert (file_info.get_name ());
-            if (new_key == null)
-                continue;
-
-            var new_file = new_scores_dir.get_child (new_key);
-            var original_file = original_scores_dir.resolve_relative_path (file_info.get_name ());
-            debug ("Moving scores from %s to %s", original_file.get_path (), new_file.get_path ());
-            original_file.copy (new_file, FileCopyFlags.NONE);
-            original_file  delete ();
-        }
-    }
-
-    private void importOldScores (File new_scores_dir) throws GLib.Error
-        /* TODO: Support importing scores from Vala games, bug #745489. */
-        requires (format == OldFormat.C_GAMES_MULTI_FILE_FORMAT)
-    {
-        importCMultiFileScores (new_scores_dir);
-    }
+    protected abstract void importOldScores (File new_scores_dir) throws GLib.Error;
 
     internal void run (string new_scores_dir) throws GLib.Error
     {